Couldn't cancel the trip even though cancellation was initiated more than 30 days out!

I booked a trip to the DR, after being contacted by Direct Buy Travel, in August, 2017, that I had unused travel certificates, for which my husband paid $2,400 at some point in the past. I couldn't asked him about it because he passed away in November, 2016. Trip was scheduled for 2/17/18 at an all inclusive resort at Puerto Plata, DR. My traveling buddy had issues getting her passport on time, we were afraid to book flights until that was resolved and I ultimately decided to cancel the trip. I called Direct Buy Travel multiple times on 1/8, 1/9 and 1/10, left v-mails but my calls were never returned. I initiated my cancellation request, in writing, on 1/11/18, well in advance of the 30 days out requirement. I tried to fax my request to a number on the paperwork I received but after multiple attempts, the fax wouldn't go through. Went online to OVC, listed in the paperwork as where to send cancellation requests, found another fax number and it went through just fine. I followed up with a letter, on 1/13/18, to OVC, also using an address listed in the cancellation paragraph of the terms and conditions. I wrongly assumed my request was being processed until my letter was returned to me on 2/1/18, "due to insufficient address". I immediately got on the phone to Direct Buy Travel and, surprise, surprise! NO record of my fax or my voice mail messages. I spent the better part of the day, on the phone, talking to no fewer than 5 people! Although I initiated my request for cancellation well in advance of the 30 day requirement, AND purchased trip cancellation protection insurance, I was told, in no uncertain terms, that I could nether cancel, change destinations or change travel dates! How very convenient that neither the fax number nor the address for OVC was correct in their "terms and conditions"! I'm out $618. 82 and vow to bad mouth Direct Buy Travel at every opportunity!